This invention relates to a magnetic filter for separating magnetic particles from fluids.
Many industrial processes generate fluids in which magnetic particles are suspended. For example, motor vehicles are commonly painted by dipping the entire body into a large paint bath. Since the body is assembled by welding and the welds are sanded, many iron particles remain loosely attached to the vehicle. When the vehicle is dipped into a paint bath, these particles mix with the paint. Accordingly, it is desirable to remove the particles from the paint continuously. Similarly, many industrial machining processes use cooling fluids, such as oil, in which magnetic particles may be suspended, and it is accordingly necessary to remove these particles from the oil.
Centrifuges and magnetic filters have been used in the prior art to remove magnetic particles suspended in fluids. Centrifuges are effective for removing large particles, but are ineffective in removing small particles, and it is desirable in many processes that small particles be removed. Magnets and magnetic filters are effective in removing small particles, but these particles remain attached to magnets, and filters incorporating magnets for the removal of magnetic particles must be cleaned at regular intervals. However, the cleaning of magnetic filters to remove magnetic particles captured by magnets within the filter is relatively expensive, since it requires substantial manual labor, requires substantial production down time, wastes a significant quantity of the fluid, and may require expensive equipment to effect cleaning.
According to the present invention, a magnetic filter consisting of multiple elongated magnetic elements which terminate in non-magnetic end portions is provided with a scraper which can be periodically actuated to scrap the particles that have been retained on the magnet in elements onto the non-magnetic end portions. The fluid being processed flushes the particles from the end portion into a flushing chamber, from which the fluid is discharged from the magnetic filter. Accordingly, the same fluid is used to remove the particles from the magnetic filter as is being processed by the magnetic filter and no disassemble is required. Labor and down time are minimized, and the waste of the processed fluid is also minimized.